Hydraulic roadbed electricity generating apparatus and method

ABSTRACT

A roadbed generator provides a roadbed collector positioned within a roadbed. The roadbed collector engages passing vehicles collecting kinetic energy therefrom, which is converted to electrical energy that is collected and passed to a load for use. In one embodiment a roadbed collector is a piston positioned below a hinged surface plate that forms part of the roadbed. Passing vehicles drive the plate and piston down into a cylinder containing hydraulic fluid, driving the hydraulic fluid from the cylinder to a hydraulic generator. A return spring coupled to the surface plate force the plate back into an elevated position after a vehicle has passed on. In some embodiments an expansion tank interposed between the cylinder and generator forces fluid back into the cylinder causing the piston to move upwardly in preparation for engaging another vehicle.

PRIORITY CLAIM

1. Field of the Invention

This invention relates generally to apparatus and methods for generating electricity and, more specifically, to apparatus and methods for generating electricity using hydraulic generators.

2. Background of the Invention

The United States has over 2.4 million miles of paved roads traveled daily by millions of automobiles. Typical automobiles weigh over two tons and therefore contain large amounts of kinetic energy as they move at high speed down the highway. At the same time many auxiliary systems associated with the roadways require electrical energy to operate. For example, many lighting systems are involved, such as street lights, semaphores, warning lights, construction lights, and the like. Other auxiliary systems are services that are provided specifically to motorists, such as emergency telephones, rest areas, weigh stations, and customs inspection stations at State and international borders.

The nation's roads extend into many remote areas. In the western United States, even highly traveled roads have long stretches extending through undeveloped areas. In such regions, it is costly and difficult to provide electrical power to provide lighting and services that may be necessary or expected. Regardless of the location of lighting systems or services, it is impossible to directly charge those who benefit therefrom. The cost of providing power to lighting systems and services must be born by the government and paid for by the public at large.

In view of the foregoing, it would be an advancement in the art to provide a system for collecting kinetic energy from passing vehicles and convert such energy to electrical energy for use in powering auxiliary roadway systems or even the power grid of a city.

SUMMARY OF THE INVENTION

The present invention comprises a roadbed generator for generating electricity from the kinetic energy of vehicles on a roadway. A roadbed generator provides a roadbed collector positioned within a roadbed. The roadbed collector typically mechanically collects kinetic energy from passing vehicles and transfers the kinetic energy to a generator. The generator converts the kinetic energy to electrical energy, which is then collected and passed to a load, such as a lighting system, emergency radio, or a power grid.

In one embodiment, the roadbed collector is a piston positioned below a hinged surface plate that directly engages passing vehicles. The surface plate typically forms part of the surface of the roadbed and the hinged edge is typically maintained flush with the surface of the roadbed. A cylinder receives a portion of the piston, such that as passing vehicles drive the plate and piston down, hydraulic fluid is driven from the cylinder and through a hydraulic generator, thereby creating electricity. The electricity is then collected and passed to a load.

In some embodiments, a return spring coupled to the surface plate forces the surface plate upward after a vehicle has passed on in preparation for engaging another vehicle. In other embodiments, an expansion tank having a spring-loaded diaphragm collects hydraulic fluid and forces the fluid back into the cylinder after a vehicle passes. Thus, the piston 60 is forced upwardly to a position suitable for engaging another vehicle. In still other embodiments, both an expansion tank and a return spring are used to recover the surface plate and piston.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.

FIG. 1 is a top schematic view of a highway having roadbed collectors, in accordance with the present invention;

FIG. 2 is a side schematic view of a roadbed collector, in accordance with the present invention;

FIG. 3 is a top schematic view of a roadbed collector and associated electrical elements, in accordance with the present invention;

FIG. 4 is a schematic view of a hydraulic generator and associated fluid handling structures, in accordance with the present invention;

FIG. 5 is side view of an alternative embodiment of roadbed collector, in accordance with the present invention;

FIG. 6 is a process flow diagram of a general method for using a roadbed collector, in accordance with the present invention;

FIG. 7 is a process flow diagram of a particular method for using a roadbed collector, in accordance with the present invention;

FIG. 8 is a side schematic of the roadbed collector of FIG. 1 in a sloped environment; and

FIG. 9 is a process flow diagram or a method for using a roadbed collector in a sloped environment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, in a typical highway environment vehicles 10 move along lanes 12, 14 headed in opposite directions along a roadbed 20. In one embodiment of the present invention, mechanical collectors, or roadbed collectors 30, are positioned within the lanes 12 and 14 and mechanically collect kinetic energy from the vehicles 10. Referring to FIG. 2, in one embodiment of a roadbed collector 30, a surface plate 40 mounts to the roadbed 20 by means of a hinge 50 and typically forms part of the surface over which the vehicles 10 drive. The surface plate 40 and hinge 50 are typically formed of steel and have sufficient strength to withstand the impact of vehicles at high speeds. The hinge 50 is typically positioned such that a vehicle will first encounter the hinged edge of the surface plate 40 and then the free end. Inasmuch as the surface plate 40 and hinge 50 form part of the surface of the roadbed 20, the hinge 50 and hinged edge of the surface plate 40 are typically flush with the surface of the roadbed 20. A piston 60 is positioned below the surface plate 40 and is depressed by the surface plate 40 as vehicles are driven thereover.

A cylinder 70 receiving the piston 60 contains hydraulic fluid, or like fluid. As the piston 60 is depressed into the cylinder, hydraulic fluid may be driven from the cylinder 70 through hydraulic lines 80 to a generator 90. The generator 90 may derive electrical energy from the forced movement of the hydraulic fluid. Hydraulic lines 80 may then carry the hydraulic fluid back to the cylinder 70 for another iteration of the process. A return spring 100 may couple the surface plate 40 to the roadbed 20 and restore the free end of the surface plate 40 to a position elevated above the roadbed 20 ready to be depressed by another passing vehicle. Alternatively, the spring 100 may secure to the piston 60, forcing the piston 60 upward, which will in turn force the surface plate 40 upward to its original position.

Referring to FIG. 3, the generators 90 may receive pressurized hydraulic fluid from multiple roadbed collectors 30 each with a corresponding piston 60 and cylinder 70. Check valves connecting each cylinder 70 to the generator 90 may ensure that backflow from one cylinder 70 to another does not occur. Electrical cables 110 may couple multiple generators 90 to a collector 120. The collector 120 may modulate the voltage from the various generators 90 to provide a substantially constant voltage output on an output line 130. A load 140 may connect to the output line 130 and make use of the electrical energy. The load 140 may be the electrical power grid of a city, traffic or street lights, an emergency satellite telephone, an emergency radio, or the like.

Referring to FIG. 4, hydraulic fluid driven from the cylinder 70 by the piston 60 may pass through a check valve 200 permitting fluid flow only in direction 210 out of the cylinder 70. The fluid may then pass by an expansion tank 220 before passing through the hydraulic generator 90. A check valve 250 permitting fluid flow only in direction 210 may be interposed between the hydraulic generator 90 and cylinder 70 to ensure hydraulic fluid only flows in one direction through the hydraulic generator 90.

In practice, a vehicle may quickly drive over the surface plate 40 whereas the viscosity of the hydraulic fluid makes forcing the fluid through the generator 90 a much slower process. Accordingly, positioning the expansion tank 220 between the cylinder 70 and generator 90 enables the fluid to quickly flow into the expansion tank 220 from the cylinder 70 in response to a passing vehicle. The diaphragm 230 and spring 240 may then force the fluid through the hydraulic generator 90 and back into the cylinder 70. In some embodiments, the spring 240 and diaphragm forcing fluid into the cylinder 70 may also serve to recover the piston 60 and surface plate 40, such that a return spring 100 is not needed.

In some embodiments, a reservoir 400 may be interposed between the check valve 250 and the hydraulic generator 90. The piston 60 may draw fluid from the reservoir 260 whereas the hydraulic generator 90 expels fluid into the reservoir 400. The Piston 60 is typically in fluid communication with the lower portion of the reservoir 400 such that hydraulic fluid, rather than air will be drawn into the cylinder 70.

Referring to FIG. 5, various embodiments of the roadbed collector 30 are possible. For example, the surface plate 40 may be dome shaped to extract energy from traffic flowing in two different directions. The surface plate 40, piston 60, cylinder 70 and return spring 100 may likewise be mounted in a ramp 300 to provide a self contained unit that may be positioned wherever needed, such as at a construction project on a remote section of highway. It will be noted that the slope 310 of the ramps is only an example. Shallower slopes 310 may be used in applications where traffic is likely to be traveling at high speeds.

Referring to FIG. 6, in one application a method 350 may be used in conjunction with a roadbed collector 30. The method 350 may include driving 360 a vehicle over a mechanical collector, such as the roadbed collector 30 described hereinabove. Driving 360 the vehicle over the mechanical collector may be an inadvertent act of the driver who happens to drive over the mechanical collector. Alternatively, driving 360 the vehicle over the mechanical collector may be intentional in order to generate electricity to operate an apparatus such as an emergency satellite telephone powered by the roadbed collector 30.

The method 350 may also include converting 370 mechanical to electrical energy. Various conversion means are contemplated by the invention. For example, the surface plate 40 may be mechanically coupled to permanent magnets such that depression of the surface plate 40 causes the magnets to move through wire coils and thereby generate electricity.

The method 350 may include collecting 380 electrical energy. The energy may be collected in a battery, high capacity capacitor, or the like. In the illustrated embodiment, collecting 380 electrical energy involves collecting energy from multiple roadbed collectors 30, which are not all simultaneously active. Accordingly, collecting 380 electrical energy may include blending the output of the various roadbed collectors 30 to provide a substantially constant voltage output.

The method 350 may include passing 390 electricity to a load, such as lighting systems or an electrical power grid. Passing 390 may take place substantially simultaneously with generation of the electricity or may be deferred. For example, the collecting step 380 may include storing the energy to be retrieved when it is needed. For example, a roadbed collector 30 may be coupled to an emergency radio or phone that is only occasionally used.

Referring to FIG. 7, the method 350 may be embodied more specifically as a method 400. The method 400 may include depressing 410 a surface plate 40 and piston 60, as by a vehicle driving thereover. Depressing 410 the pistion 60 leads to forcing 420 hydraulic fluid flow. The method 400 may then include generating 430 electricity from the fluid flow, such as by a hydraulic generator 90. The electrical energy may then be collected 380 and passed 390 to a load as in the method 350 of FIG. 6. The method 400 may also include recovering 440 the piston 60 and surface plate 40. Recovering 440 typically includes forcing hydraulic fluid back into the cylinder 70 causing the piston 60 and surface plate 40 to move to their original position prior to passage of a vehicle thereover. In one embodiment, recovering 440 the piston may include moving the piston 60 and surface plate 40 upwardly by a return spring 100 that is compressed when the vehicle depresses the piston 60. As the piston 60 moves upward, it may then draw hydraulic fluid back into the cylinder 70 in preparation for another iteration of the method 400.

Referring to FIG. 8, a roadbed collector 30 may be used to convert potential gravitational energy into electrical energy. As vehicles descend hills, gravity typically powers movement of the vehicle as opposed to the vehicle's engine. Accordingly, a roadbed collector 30 may be used to harvest a portion of the kinetic energy so generated as a clean source of energy. For example, the roadbed collector 30 may be mounted in a roadbed 20 having a downward slope 500. The surface plate 40 may mount to the surface having its hinge 50 mounted uphill from the free end.

In some embodiments of the invention, a lip 501 may be formed on or secured to the free end of the surface plate 40. The lip 501 may serve to prevent tire damage to those driving over the free end of the surface plate 40 first, rather than the fixed end. The lip 501 may be planar or arcuate having a radius of curvature approximating the distance between the fixed end of the surface plate 40 and the free end.

Referring to FIG. 9, while still referring to FIG. 8, as a vehicle descends the roadbed 20, a process 510 may occur. The process 510 may include converting 520 the potential gravitational energy of the vehicle to kinetic energy as the car moves down the slope under the influence of gravity. The process 510 may then include converting 530 a portion of the kinetic energy to electrical energy by depressing the surface plate 40 and piston 60 and causing forced hydraulic fluid flow through the hydraulic generator 90 as illustrated in the process 400. The electrical energy from the hydraulic generator may then be collected 380 and passed 390 to a load is in the methods 350 and 400 of FIGS. 6 and 7.

While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the the preferred embodiment. Instead, the invention should be determined entirely to the claims that follow. 

1. A generator for a roadbed having a driving surface comprising: a surface element at least partially moveable relative to the roadbed; a mechanical collector positioned below the driving surface and being actutated by the surface element; and a generator coupled to the mechanical collector to convert mechanical movement of the mechanical collector into electrical energy.
 2. The generator of claim 1, wherein the generator is electrically coupled to a power grid.
 3. The generator of claim 1, wherein the generator is electrically coupled to an auxiliary roadway system.
 4. The generator of claim 1, wherein the surface element comprises a plate having a fixed end pivotally secured to the roadbed.
 5. The generator of claim 4, wherein the plate comprises a free end having a lip extending downwardly therefrom.
 6. The generator of claim 4, wherein the mechanical collector comprises a piston and cylinder, the piston being slidably positioned within the cylinder and engaging the plate to be actuated thereby, the generator comprising a hydraulic generator in fluid communication with the cylinder.
 7. The generator of claim 6, wherein a first channel connects the cylinder to an inlet of the hydraulic generator, an expansion tank being connected to the first channel.
 8. The generator of claim 7, further comprising a reservoir in fluid communication with an outlet of the hydraulic generator.
 9. The generator of claim 8, wherein the reservoir is in fluid communication with the cylinder having a first check valve interposed therebetween permitting outward flow from the reservoir.
 10. The generator of claim 9, further comprising a second check valve interposed between the cylinder and the expansion tank permitting outward flow from the cylinder.
 11. The generator of claim 1, wherein the surface element comprises a domed structure having an uppermost portion thereof positionable above the roadbed.
 12. The generator of claim 10, wherein the mechanical collector comprises a piston and cylinder, the piston being slidably positioned within the cylinder and engaging the domed structure to be actuated thereby, the generator comprising a hydraulic generator in fluid communication with the cylinder.
 13. A generator for a roadbed, comprising: a surface element hingedly secured to the roadbed; a piston engaging the surface element to be actuated thereby; a cylinder receiving a portion of the piston, the piston being slidable within the cylinder; and a hydraulic generator in fluid communication with the cylinder.
 14. The generator of claim 13, wherein a first channel connects the cylinder to an inlet of the generator, an expansion tank being connected to the first channel.
 15. The generator of claim 14, further comprising a reservoir in fluid communication with an outlet of the generator.
 16. The generator of claim 15, wherein the reservoir is in fluid communication with the cylinder having a check valve interposed therebetween permitting outward flow from the reservoir.
 17. The generator of claim 16, further comprising a check valve interposed between the cylinder and the expansion tank permitting outward flow from the cylinder.
 18. A method for collecting electricity from travel over a roadbed, the method comprising: providing a roadbed collector positioned within the roadbed; providing a generator coupled to the roadbed collector to receive kinetic energy therefrom and convert the kinetic energy to electrical energy; passing a vehicle over the roadbed collector, the roadbed collector directly engaging a portion of the vehicle; and actuating the generator to generate electrical energy.
 19. The method of claim 18, further comprising supplying the electrical energy to a power grid.
 20. The method of claim 19, further comprising, supplying the electrical energy to an auxiliary roadway system. 